The present invention is related to systems and methods of constructing highway bridges, traffic overpasses, causeways and the like, and more particularly, to a bridge constructing system using light weight lifting equipment and modular light weight structural elements, wherein the system integrates the lifting equipment with the structure being erected using the structure as a crane platform.
Construction of highway bridges and causeways requires special high capacity lifting equipment, typically cranes. In most cases, lifting is performed by cables or hydraulic jacks, providing three or one degrees of freedom movement, respectively. Precise load positioning and orientation of the load (roll, pitch and yaw) is achieved by pulling with auxiliary tie lines or pushing with poles, jacks or other external devices.
Lifting, carrying and final positioning of a payload that is not fully constrained results in pendulation and rotation of the payload, which reduces safety, requires more time to damp motion, and in harsh environmental situations, such as high winds, may cause shutdown and postponement of the lifting operation.
Feasibility, cost and construction time for erecting highway bridges and causeway structures is typically governed by the assembly method, capacity of available lifting equipment, weight and number of the structural elements, organization of a staging-storage area and transporting the structural elements and lifting equipment from the production site to the erection site.
Use of large preassembled structural elements can substantially reduce construction time and cost. However, handling of the large structural elements typically requires heavy lifting equipment, such as cranes having spreader bars. If the assembly cranes are heavier than the load that the bridge or causeway is intended to carry, the assembled structure may have to be overdesigned to support the assembly equipment.
The following publications are related to construction of bridge structures.
U.S. Pat. No. 3,845,515 to Gelhard et al. discloses a system for self-advancing construction of a conduit line. A railway is mounted on each side of the conduit. An assembly scaffolding capable of motion is suspended from the rails and is provided with a progressing erection component cantilevered to overhang the most forward assembled conduit section. The scaffolding accepts construction components and progressively erects the components along an intended route. The assembly scaffold is comprised of several connected, mutually supported and series-arrayed assembly sections. The front section of the assembly structure is developed into a cantilevered erecting section, while the most rearward assembly section is developed into a cantilevered material receiving section. Sections in between the front and rear cantilever sections are provided with controlled suspensions. An assembly scaffold consisting of several sections is thus suspended from its middle sections on travel rails of the previously erected pipe railroad section, and may be supplied with construction material from the rear. The materials are then transported to the front progressing sections of the structure where they are used by the cantilevered construction equipment to construct a further forward section of the pipe railroad. When construction of that section is completed, the entire assembly scaffold may move forward by the corresponding new segment, and a new section may be begun.
U.S. Pat. No. 3,385,455 to Dal Pont discloses an apparatus for lifting, horizontally transporting and installing heavy loads, such as metal lattice trusses, between spaced apart vertical support points. The apparatus comprises spaced apart first and second vertical support means against which rests each end of a horizontally extending boom and respective tackle means supported from spaced apart points along the boom. The boom and support means constitute a rigid stationary structural assembly while a load is being moved between the vertical support points. The assembly is transferable as a unit to other locations.
U.S. Pat. No. 4,282,978 to Zambon discloses a bridge crane comprising a framework consisting of a pair of parallel trusses interconnected by end portals and long enough to extend across three piers. Each truss has a bottom stringer formed on its underside with tracks engaged above each pier by rollers mounted on a pair of rocker arms, which are part of an undercarriage movable on transverse guide rails. Top stringers of the trusses support a trolley carrying hoists for raising and lowering transported castings. Longitudinal movement of the framework relative to the piers is brought about by a motor-driven capstan carried on the framework.
U.S. Pat. No. 3,902,212 to Muller discloses a device for use in building the superstructure of a multispan civil engineering work, such as a bridge or elevated road. The superstructure comprises at least one two-arm beam extending in a longitudinal direction substantially symmetrically on both sides of a previously erected pier. The device is comprised of a raised elongated scaffold E having a median support adapted to rest on the pier. The scaffold includes booms 1, 2 and 3. The booms 1 and 2 constitute rolling tracks for carriages 4 and 5.
European Publication 0 102 900 A2 discloses a beam positioning system having two parallel horizontal frames spanning over three columns. Each frame has a top rolling track for mobile bogies that move astride the frames and carry beam lifters. Each frame has a parallel bottom rolling track for rollers at the top of each column.
Japanese Publication 1-310003 (A) discloses a bridge building method using a traveling frame lockable on an existing beam, a lifter type crane, and a means to hang/support a beam block from the lifter type crane.
Soviet Publication SU 908989 discloses a gantry type bridge erection crane including a load carriage supporting beam 2, hinged and fixed legs 8 and 10 and an operating mechanism. After bridge supports and beams 12 and 13 are erected, crane columns 7, in the next span are jacked up and mounted on the erected bridge beams. The crane beam is then transferred to a new erection position, the crane columns lowered, and freed temporary supports 4 moved forward.
Soviet Publication SU 1096328 A discloses a bridge span assembly method using mobile support gantries of adjustable height.
U.S. Pat. No. 3,027,633 to Murphy discloses a method and apparatus for bridge construction in which a light-weight, temporary erection span 11 is erected on a barge 12, hoisted into position between two bridge piers, and used as a working platform for erecting a bridge span. The method includes a deck traveler 17 equipped with two stiff-leg derricks 17a and 17b mounted on a completed bridge span 18 and moving on skid beams mounted on the upper floor beams of the completed bridge span.
U.S. Pat. No. 3,571,835 to Buechler discloses an apparatus for concreting multiple section elevated structures. The apparatus comprises two girders that are movable relative to one another. One of the girders is a scaffold girder, and the other is an advancing girder that supports the scaffold girder as it is advanced.